Many food products are perishable and also fragile, that is, subject to becoming crushed or pulverized if subjected to trauma. Such products include, for example, breakfast cereal, candies, and snack foods. Breakfast cereal has traditionally been shipped to the consumer in paperboard boxes having a resealable bag liner made of waxed paper, plastic film, or metal foil. The box protects the contents against being crushed, and the liner is impermeable to moisture and moist outside air that could make the product turn stale.
Many problems and inefficiencies with such conventional packages have been tolerated by the industry. The outer paperboard box is subject to degradation if it becomes wet, and even though the contents may remain dry within the inner bag, the box may lose its structural integrity and fail to protect the product against crushing. The outer paperboard box is also subject to infestation by pests. Graphics printed on the box exterior are also subject to degradation as a result of moisture or abrasive handling.
Manufacturers may resort to forming the box from specially treated waterproof board. This practice significantly increases the cost of the container, as it results in two separate sealing envelopes, one inside and one outside the box. Consumers have been known to provide a second, outer seal by placing the box after opening into a sealable plastic bag.
Conventional cereal containers of the type described require multiple-step loading and closing procedures. One option is to insert the inner bag into the box, hold open the bag while filling it, seal the bag within the box, and finally glue the paperboard top closure panels. Holding a flimsy bag open within the box is difficult, and the equipment using this technique is slow. Another option is to fill the bag and seal it, then drop the bag into the box and seal the closure panels. This requires handling of the non-rigid bag with its unprotected fragile contents, which can lead to crushing of some of the product. It is a difficult and slow process to fit a non-shaped bag into a square box having the same volume, so the full bag must be smaller than the box. Thus, the capacity of the box is underutilized.
When the consumer is ready to open the container, the closure panels are separated and the top of the inner bag is opened. The bag may be formed by creating fin seals along the bottom and top of a tubular length of the film used to make the bag. For reclosing, two steps are required. Conventional containers are typically provided with closure panels having a slit in one panel and a tuck tab in the other panel. The consumer folds or rolls the bag to reclose it, often forming an imperfect seal. Then he or she closes the box panels and inserts the tuck tab into the slit.
Thus, there is a need in the art for a container for perishable, fragile products which is easy to load rapidly, protects the exterior of the paperboard box, avoids duplicating the sealing function, and closes and reseals the container in a single step.